Neuronal Morphology Enhances Robustness to Perturbations of Channel Densities

Abstract

Biological neurons show significant cell-to-cell variability but have the striking ability to maintain their key firing properties in the face of unpredictable perturbations and stochastic noise. Using a population of multi-compartment models consisting of soma, neurites, and axon for the lateral pyloric (LP) neuron in the crab stomatogastric ganglion, we explored how rebound bursting is preserved when the 14 channel conductances in each model are all randomly varied. The soma-axon coupling is critical for the ability of the axon to spike during bursts and consequently determines the set of successful solutions. When the coupling deviates from a biologically realistic range, the neuronal tolerance of conductance variations is significantly lessened. Thus, the gross morphological features of these neurons enhance their robustness to perturbations of channel densities and expands the space of individual variability that can maintain a desired output pattern.